ABSTRACT
The present study was carried out to determine the possible bioactive components (steroids) of Cenchrus setigerus using GC-MS analysis and in vivo estimation of metabolites (total soluble sugar, soluble protein, proline and total phenolics), photosynthetic pigments (chlorophyll-a, chlorophyll-b and carotenoids) of seedlings and antimicrobial activity of extracts in various polar solvents from the leaves of C. setigerus. Antimicrobial activity was evaluated against three Gram-negative bacteria, including Proteusmirabilis, Klebsiella pneumonia and Agrobacterium tumefaciens andone fungus Aspergillus niger using 'disc diffusion' method, followed by the determination of minimum inhibitory concentrations (MIC) by broth dilution method. Results revealed the presence of some steroids in the isopropyl alcohol extract of C. setigerus:which are (22E)-stigmasta-4,22-dien-3-one(4.93%), δ4-sitosterol-3-one (stigmast-4-en-3-one) (4.31%), fagarsterol (lupeol) (1.25%) and ethyl iso-allocholate (0.32%). Total soluble sugars and chlorophyll-a were also recorded to be highest. The highest activity was exhibited by the isopropyl alcohol and ethyl acetate extract against P. mirabilis.
ABSTRACT
The ripen fruit extracts of Withania somnifera were evaluated against medically important bacteria viz. Proteus merabilis, Klebsiella pnemoniae, Agerobacterium tumefaciens (plant pathogen) and one fungi Aspergillus niger. The dried and powdered ripen fruits were successively extracted with a series of non polar to polar solvents using soxhlet assembly. The antimicrobial assay was done by both disc diffusion and broth dilution methods. Glacial acetic acid extract of W. somnifera show highest activity against A. tumefaciens (plant pathogen) and water extract against K. pnemoniae to varying degrees in the terms of high inhibition zone and activity index. A. tumefaciens was the most susceptible organism in compare to the other organism. Gentamycin and Ketoconazole, the standard antibacterial and antifungal used was effective against the bacteria and fungi. The extract of W. somnifera also significantly (P>0.005) inhibited the bacterial and fungal growth. The inhibitory effect is very identical in magnitude and comparable with that of standard antibiotics used.